Resin Bonded Abrasive

ABSTRACT

A superabrasive resin product includes a superabrasive grain component, an oxide component, and a continuous phase defining a network of interconnected pores. The oxide component consists of an oxide of a lanthanoid, and the continuous phase includes a thermoplastic polymer component. The superabrasive grain component and the oxide component are distributed in the continuous phase.

CROSS-REFERENCE TO RELATED APPLICATION(S)

The present application is a continuation of U.S. patent applicationSer. No. 13/504,917, filed Apr. 27, 2012, entitled “Resin BondedAbrasive” naming Inventors Ramanujam Vedantham and Rachana Upadhyaywhich in turn is a National Stage application of PCT ApplicationPCT/US2010/054329, filed Oct. 27, 2010, entitled “Resin Bonded Abrasive”naming Inventors Ramanujam Vedantham and Rachana Upadhyay, which in turnclaims priority to U.S. Provisional Patent Application Ser. No.61/255,256 filed on Oct. 27, 2009, entitled “Resin Bonded Abrasive”naming inventors Ramanujam Vedantham and Rachana Upadhyay, which are allincorporated by reference herein in their entirety.

TECHNICAL FIELD

The disclosure generally relates to a superabrasive product, asuperabrasive product precursor to a superabrasive product, and to amethod of making a superabrasive product.

BACKGROUND ART

With the global trend of miniaturization, electronic devices arebecoming smaller. For semiconductor devices that operate at high powerlevels, wafer thinning improves the ability to dissipate heat. As finalthickness is decreased, the wafer progressively becomes weaker tosupport its own weight and to resist the stresses generated by postbackgrinding processes. Thus, it is important to reduce the damagescaused by backgrinding and improve quality.

The original thickness of silicon wafers during chip fabrication is725-680 μm for 8 inch wafers. In order to obtain faster and smallerelectronic devices, the wafers need to be thinned before dicing intoindividual chips. The grinding process consists of two steps. First, acoarse abrasive wheel grinds the surface to around 270-280 μm, butleaves behind a damaged Si surface, the (backside) surface of the Siwafer. Then, a fine abrasive wheel smoothes part of the damaged surfaceand grinds the wafer to 250 μm. Wafers with thicknesses down to 100-50μm are virtually a standard requirement for some IC chip applications.For a long time now the most common thickness in smart cards has beenabout 180 μm. However, the thinner IC chips are becoming more common insmart cards. Therefore, a need exists for improved grinding toolscapable of roughing or finishing hard work pieces, as well as formethods of manufacturing such tools.

DISCLOSURE OF INVENTION

In an embodiment, a superabrasive resin product can include asuperabrasive grain component, an oxide component, and a continuousphase. The oxide component can include an oxide of a lanthanoid, and thecontinuous phase can include a thermoplastic polymer component and athermoset polymer component. The continuous phase can define a networkof interconnected pores. The superabrasive grain component and the oxidecomponent can be distributed in the continuous phase.

In a particular embodiment, the lanthanoid can include an element havingan atomic number not less than 57 and not greater than 60, such aslanthanum, cerium, praseodymium, and neodymium. More particularly, thelanthanoid can include cerium, and even can consist essentially ofcerium. The oxide of the lanthanoid can be present in an amount in arange of between about 0.05 and about 10 volume percent of thesuperabrasive resin product.

In another embodiment, a superabrasive product precursor can include asuperabrasive grain component, an oxide component, a bond component, anda polymeric blowing agent of encapsulated gas. The oxide component caninclude an oxide of a lanthanoid.

In yet another embodiment, a method of forming a superabrasive productcan include combining a superabrasive, an oxide component consisting ofan oxide of a lanthanoid, a bond component, and a polymeric blowingagent of encapsulated gas, and heating the combined superabrasive, bondcomponent, oxide component, and polymeric blowing agent to a temperatureand for a period of time that causes release of at least a portion ofthe gas from encapsulation within the blowing agent.

In still another embodiment, a method of back grinding a wafer caninclude providing a wafer, and back grinding the wafer to an averagesurface roughness (Ra) of not greater than 25 angstroms. Grinding can beperformed using a superabrasive resin product. The superabrasive resinproduct can include a superabrasive grain component, an oxide componentconsisting of an oxide of a lanthanoid, and a continuous phase. Thecontinuous phase can include a thermoplastic polymer component and athermoset polymer component, and the superabrasive grain component andthe oxide component can be distributed in the continuous phase.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure may be better understood, and its numerousfeatures and advantages made apparent to those skilled in the art byreferencing the accompanying drawings.

FIG. 1 is a cross-section of an embodiment of a superabrasive resintool.

FIGS. 2 and 3 are scanning electron micrographs of an exemplarysuperabrasive product.

The use of the same reference symbols in different drawings indicatessimilar or identical items.

DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

In an embodiment, the superabrasive product can include a superabrasivegrain component, an oxide component, and a continuous phase thatincludes a thermoplastic polymer component and a thermoset resincomponent, wherein the superabrasive grain component and the oxidecomponent is distributed in the continuous phase. The superabrasivegrain component can be, for example, diamond, cubic boron nitride,zirconia, or aluminum oxide. The thermoset resin component can include,for example, phenol-formaldehyde. The thermoplastic polymer componentcan include, for example, polyacrylonitrile and polyvinyledene.Preferably, a superabrasive product can have an open-porous structure,whereby a substantial portion of the pores of the product areinterconnected and in fluid communication with a surface of thesuperabrasive product.

“Superabrasive,” as that term is employed herein, means abrasives havinghardness, as measured on the Knoop Hardness Scale of at least that ofcarbon boron nitride (CBN), i.e., a K100 of at least 4,700. In additionto cubic boron nitride, other examples of superabrasive materialsinclude natural and synthetic diamond, zirconia and aluminum oxide.Suitable diamond or cubic boron nitride materials can be crystal orpolycrystalline. Preferably, the superabrasive material is diamond.

The superabrasive material can be in the form of grain, also known as“grit.” The superabrasive grain component can be obtained commerciallyor can be custom-produced. Generally, the superabrasive can have anaverage particle size in a range of between about 0.25 microns and 50microns. Preferably, the particle sizes can be in a range of betweenabout 0.5 microns and 30 microns. In particular embodiments, the averageparticle size of the grit can be in a range of between about 0.5 micronsand 1 micron, between about 3 microns and about 6 microns, such asbetween about 20 microns and 25 microns.

In one embodiment, the superabrasive grain component can be present inan amount of at least 20% by volume of the superabrasive tool. Inanother embodiment, the superabrasive grain component can be present inan amount in a range of between about 3% and about 25% by volume of thesuperabrasive tool, more preferably between about 6% and about 20% byvolume of the superabrasive tool. In still another embodiment, the ratioof superabrasive grain component to continuous phase of thesuperabrasive product can be in a range of between about 4:96 and about30:70 by volume, or more preferably in a range of between about 15:85and about 22:78 by volume.

In an embodiment, the superabrasive product can include an oxide of alanthanoid. The oxide of the lanthanoid can be a compound or complexformed of a lanthanoid element and oxygen. The lanthanoid can include anelement of the periodic table having an atomic number of not less than57 and not greater than 60, such as lanthanum, cerium, praseodymium, andneodymium. Preferably, the lanthanoid can include cerium and may evenconsist essentially of cerium. The oxide of the lanthanoid can be in anamount in a range of between about 0.05 and about 10 volume percent ofthe superabrasive product, such as between about 1.0 and about 4 volumepercent.

The oxide component can have an average particle size of not greaterthan about 30 microns, such as not greater than about 25 microns, notgreater than about 20 microns, not greater than about 18 microns, oreven not greater than about 15 microns. In certain instances, the oxidecomponent can have an average particle size within a range between about0.1 μm and about 30 μm, such as within a range between about 0.1 micronsand about 25 microns, between about 0.1 microns and about 20 microns,between about 0.1 microns and about 18 microns, or even between about 1micron and about 15 microns.

In an embodiment, the superabrasive product can include a network ofinterconnected pores. The pores can include large pores having a size ofbetween about 125 microns and about 150 microns, small pores having asize of between about 20 microns and about 50 microns, intermediatepores having a size of between about 85 microns and about 105 microns,or any combination thereof. The pores can have a multimodal sizedistribution with at least two modes, such as at least three modes. Asused herein, a multimodal size distribution is a continuous probabilitydistribution function of particle sizes or pore sizes comprised of twoor more modes. Each mode appears as a distinct local maximum in theprobability distribution function. The multimodal distribution can has amode of between about 125 microns and about 150 microns, a mode havingan average size of between about 85 microns and about 105 microns, amode having an average size of between about 30 microns and about 50microns, or any combination thereof

Porosity plays an important role in grinding. Porosity controls thecontact area between the work piece and the composite microstructure.Porosity facilitates movement of coolant around the microstructure tokeep the grinding surface temperature as low as possible. It isimportant to understand different structures created by using aplurality of different size pore inducers.

Relatively large, e.g., 120-420 μm diameter physical blowing agentsgenerally can yield big pores with relatively few strong bridges. On theother hand, relatively small physical blowing agents between the sizesof 10-80 μm can create a higher number of smaller bridges. A goodbalance of smaller and larger pore inducers produces a microstructurewith advantageous properties found in both microstructures producedexclusively with larger pore inducers and microstructures producedexclusively with smaller pore inducers.

In an embodiment, a superabrasive product can include a superabrasivegrain component, an oxide component, and a continuous phase. Thecontinuous phase in which the superabrasive grain component and theoxide component can be distributed can include a thermoplastic polymercomponent. Generally, the superabrasive tool can be a bonded abrasivetool, as opposed to, for example, a coated abrasive tool.

Examples of suitable thermoplastic polymer components can include atleast one member selected from the group consisting ofpolyacrylonitrile, polyvinyledene, polystyrene andpolymethylmethacrylate (PMMA). Examples of preferable thermoplasticpolymer components can include polyacrylonitrile and polyvinyledenechloride. In a particularly preferred embodiment, the continuous phaseof the superabrasive product can include a combination ofpolyacrylonitrile and polyvinyledene chloride. In one embodiment, theweight ratio of polyacrylonitrile and polyvinyledene chloride can be ina range of between about 60:40 and about 98:2. In a particularlypreferred embodiment, the ratio between polyacrylonitrile andpolyvinyledene chloride can be in a ratio of between about 50:50 and90:10.

The continuous phase of the superabrasive product can also include athermoset polymer component. Examples of suitable thermoset polymercomponents for use in the continuous phase of the superabrasive productcan include polyphenolformaldehyde polyamide, polyimide, andepoxy-modified phenol-formaldehyde. In a preferred embodiment, thethermoset polymer component can be polyphenol-formaldehyde.

The volume ratio between thermoplastic polymer component and thermosetpolymer component in the continuous phase typically can be in a range ofbetween about 80:15 and about 80:10. In a particularly preferredembodiment, the volume ratio between the thermoplastic polymer componentand thermoset polymer component of the continuous phase can be in arange of between about 70:25 and about 70:20. In another preferredembodiment, the volume ratio of thermoplastic to thermoset polymer inthe continuous phase can be in a range of between about 50:30 and about50:40.

Other components of the superabrasive product can include, for example,inorganic fillers like silica, silica gel in a range of between about0.5 volume percent and about 3 volume percent.

In another embodiment, a superabrasive product precursor to asuperabrasive product can include a superabrasive grain component, anoxide component, a bond component, and a polymer blowing agent, whereinthe polymer blowing agent encapsulates gas. A preferred superabrasivegrain component of the superabrasive product precursor is diamond. Theoxide component can be an oxide of a lanthanoid. The bond component canbe a thermoset resin component that will polymerize during conversion ofthe superabrasive product precursor to a superabrasive product. Examplesof suitable bond components can include those known in the art, such asphenol-formaldehyde, polyamide, polyimide, and epoxy-modifiedphenol-formaldehyde.

In one embodiment, the blowing agent can include discrete particles, atleast a portion of the particles having a shell that encapsulates gas.Generally, at least a portion of the shells include a thermoplasticpolymer. Examples of suitable plastic polymers includepolyacrylonitrile, polyvinyledene, such as polyvinyledene chloride,polystyrene, nylon, polymethylmethacrylate (PMMA) and other polymers ofmethylmethacrylate. In one embodiment, the discrete particles can be ofat least two distinct types, wherein each type includes a differentcomposition of thermoplastic shell. For example, in one embodiment, atleast one type of discrete particle has a thermoplastic shell thatsubstantially includes polyacrylonitrile. In another embodiment, atleast one type of discrete particle has a thermoplastic shell thatsubstantially includes polyvinyledene chloride. In still anotherembodiment, at least one type of discrete particle of the blowing agenthas a thermoplastic shell that substantially includes polyacrylonitrileand another type of discrete particle of the blowing agent has athermoplastic shell that substantially includes polyvinyledene chloride.In yet another embodiment, at least three distinct types of discreteparticles can be present, each distinct type of discrete particleshaving a thermoplastic shell including a different weight ratio ofpolyacrylonitrile and polyvinyledene chloride.

Typically, polymeric spheres that encapsulate gas, such as those thatinclude at least one of polyacrylonitrile, polyvinyledene chloride,polystyrene, nylon and polymethylmethacrylate (PMMA), and other polymersof methylmethacrylate (MMA), and which encapsulate at least one ofisobutane and isopentane, are available commercially in “expanded” and“unexpanded forms.” “Expanded” versions of the spheres generally do notexpand significantly during heating to a temperature that causes thepolymeric shells of the spheres to rupture and release the encapsulatedgas. “Unexpanded” versions, on the other hand, do expand during heatingto temperatures that cause the polymeric shells to rupture. Either typeof polymeric sphere is suitable for use as a blowing agent, althoughexpanded polymeric spheres are preferred. Unless stated otherwise,reference to sizes of polymeric spheres herein are with respect toexpanded spheres.

Often, suitable polymeric spheres that are commercially available aretreated with calcium carbonate (CaCO3) or silicon dioxide (SiO2).Examples of suitable commercially available polymeric spheres includeExpanded DE 40, DE 80 and 950 DET 120, all from Akzo Nobel. Otherexamples include Dualite E135-040D, E130-095D and E030, all from Henkel.

In another embodiment, the blowing agent of the superabrasive productprecursor includes discrete particles of a shell that includes acopolymer polyacrylonitrile and polyvinyledene chloride. The ratio byweight of polyacrylonitrile to polyvinyledene chloride can be, forexample, in a range of between about 40:60 and about 99:1. The averageparticle size of the blowing agent can be, for example, in a range ofbetween about 10 microns and about 420 microns. In a specificembodiment, the average particle size of a blowing agent can be in arange of about 20 microns and 50 microns. In this embodiment, the weightratio of polyacrylonitrile to polyvinyledene can be, for example, in arange of between about 40:60 and 60:40. Preferably, the weight ratio ofpolyacrylonitrile to polyvinyledene chloride in this embodiment is about50:50.

In another embodiment, the average particle size of the blowing agent isin a range of between 85 microns and about 105 microns. In thisembodiment, the weight ratio of polyacrylonitrile and polyvinyledenechloride preferably is in a range of between about 60:40 and about80:20, with a particularly preferred ratio of about 70:30.

In still another embodiment, the average particle size of the blowingagent is greater than about 125 microns. In this embodiment, the weightratio of polyacrylonitrile to polyvinyledene chloride preferably is in arange of between about 92:8 and about 98:2, with a particularlypreferred ratio of about 95:5.

In an embodiment, the blowing agent can include discrete particleshaving a multimodal size distribution. The multimodal size distributioncan include a mode of between about 125 microns and about 150 microns, amode of between about 85 microns and about 105 microns, a mode ofbetween about 30 microns and about 50 microns, or any combinationthereof.

Examples of encapsulated gas of the discrete particles include at leastone member selected from the group consisting of isobutane andisopentane. In the embodiment where suitable gases include at least oneof isobutane and isopentane, the size of the discrete particlespreferably is in a range of between about 8 microns and about 420microns, and the wall thickness of the discrete particles encapsulatingthe gas preferably is in a range of between about 0.01 microns and about0.08 microns.

The ratio of discrete bodies of the blowing agent to bond component inthe superabrasive product precursor generally is in a range of betweenabout 2:1 and about 30:35 by volume. In a specific embodiment, thevolumetric ratio is 80:15, and in another embodiment the volumetricratio is 70:25.

In still another embodiment, a method for forming a superabrasiveproduct can include combining a superabrasive, a bond component, anoxide component, and a polymer blowing agent of encapsulated gas. Thecombined superabrasive, bond component, oxide component, and polymerblowing agent are heated to a temperature and for a period of time thatcauses release of at least a portion of the gas from encapsulationwithin the blowing agent. Typically, the superabrasive is diamond, thebond includes a thermoset, such as phenol-formaldehyde, the oxidecomponent is an oxide of a lanthanoid, and the blowing agent ofencapsulated gas includes a thermoplastic shell of at leastpolyacrylonitrile and polyvinyledene chloride, encapsulating a gas of atleast one of isobutane and isopentane.

The combined superabrasive, bond component, oxide component, and polymerblowing agent are heated to a temperature and for a period of time thatcauses at least a substantial portion of the encapsulated gas to bereleased from the superabrasive product precursor, whereby thesuperabrasive product formed has a porosity that is substantially anopen porosity. “Open porosity,” as defined herein, means that at least aportion, or a substantial portion, of the pores are in fluidcommunication with each other and with the surface of the superabrasiveproduct. In one embodiment, where between about 70% and about 90% of thevolume of the superabrasive product is occupied by pores, the productwill be essentially all openly porous. Where the superabrasive producthas porosity in a range of between about 40% and about 70%, then aportion of the pores will be closed and the remainder open. In stillanother embodiment, where porosity is in a range of between about 20%and about 40%, essentially all of the pores will be closed.

In one embodiment, the combined superabrasive, bond component, oxidecomponent, and polymer blowing agent in the form of a superabrasiveproduct precursor, is heated while the superabrasive product precursoris under a positive gauge pressure. Typically, the polymer blowing agentincludes a thermoplastic polymer while the bond component includes athermoset polymer. In one embodiment, the superabrasive productprecursor is preheated to a first temperature of at least about 100° C.under pressure of at least two tons. The superabrasive product precursoris then heated from the first temperature to a second, soak temperature,of at least about 180° C. The superabrasive product precursor is thenmaintained at the soak temperature for at least about 15 minutes tothereby form the superabrasive article. Typically, the superabrasiveproduct precursor is heated to the first temperature, the second soaktemperature, and maintained at the soak temperature while thesuperabrasive product precursor is in a mold, such as is known in theart.

After maintaining the superabrasive product precursor at the soaktemperature for a period of time sufficient to form the superabrasiveproduct, the superabrasive product is cooled from the soak temperatureto a first reduced temperature, in a range of between about 100° C. andabout 170° C. over a period of time in a range of between about 10minutes and about 45 minutes. The superabrasive product typically isthen cooled from the first reduced temperature to a second reducedtemperature in a range of between about 30° C. and about 100° C. over aperiod of time in a range of between about 10 minutes and about 30minutes.

Typically, the superabrasive product is cooled to the first reducedtemperature by air cooling and then cooled from the first reducedtemperature to the second reduced temperature by liquid cooling. Thesuperabrasive article is then removed from the mold after being cooledto the second reduced temperature.

In an embodiment, the superabrasive article can be subjected to anoptional post-bake process after cool. For example, the superabrasivearticle can be heated to a temperature of at least about 180° C. for aperiod of several hours, such as at least about 5 hours, even at leastabout 10 hours.

In an embodiment, the superabrasive product exhibits strengthcharacteristics, characteristic of a blend of thermoset andthermoplastic polymers. Further, the superabrasive resin product canbind superabrasive grain components, such as diamonds, very effectively,enabling fabrication tools having a wider range of grain componentparticle size. In addition, the tools can have a relatively highporosity, thereby enabling the tools to be cooled more effectively. As aconsequence, grinding of a work piece can be better controlled and wearof the grinding tool is significantly reduced. The superabrasive toolcan be fabricated relatively easily, at lower temperatures, for shortercycles, and under more environmentally friendly conditions, than iscommon among methods required to fabricate other types of superabrasivetools, such as tools that employ a vitreous bond. Examples of thesuperabrasive tools can include fixed abrasive vertical (FAVS)spindle-type tools, wheels, discs, wheel segments, stones and hones. Inone embodiment, the superabrasive product can be employed in fixedabrasive vertical spindle (FAVS)-type applications.

In one preferred embodiment, the superabrasive resin product is a fixedabrasive vertical spindle (FAVS). An example of a FAVS, is shown inFIG. 1. As shown in the FIG. 1, tool 10 is configured as a wheel havinga base 12 about an axis 14. Raised perimeter 16 of wheel supportsabrasive segment 18 about the perimeter of base 12. Abrasive segment isone embodiment of a superabrasive product. Typically, base will have adiameter in a range of between about six inches and about twelve inches;the height of the abrasive segment will be in a range of between about 2millimeters (mm) and about 10 millimeters, such as in a range of betweenabout 5 millimeters and about 8 millimeters, and have a width of betweenabout 2 millimeters and about 4.5 millimeters. Wheels, as described withreference to FIG. 1, are suitable for wafer grinding by rotation abouttheir axis. In a direction counterclockwise to a rotation of the axis ofa wafer being ground by the tool.

A Surface Roughness Index can be determined by back grinding a series ofsilicon wafers. During back grinding, the superabrasive can be rotatedat a speed of 5500 rpm while contacting the surface of the wafer withthe chuck table rotating at a speed of 80 rpm. The wafer can be groundfrom a starting thickness of 450 microns to a final thickness of 430microns. The feed rate of the superabrasive can be 0.80 microns/secuntil the wafer thickness is reduced to about 434 microns. The feed ratecan then be reduced to 0.50 microns/sec until the wafer thickness ifabout 430 microns. Upon reaching a thickness of about 430 microns, thefeed rate can be reduced to 0.10 microns/sec until the final thicknessof 430.0 is achieved.

The Ra (arithmetic average of the roughness profile) of the surface ofthe wafer can be determined at five points on the wafer including thecenter and four locations approximately 1 cm from the edge andapproximately 90° apart. The Ra for each point can be determinedoptically at 40X magnification. The readings for each wafer can beaveraged to determine the average Ra of each wafer. The average Ra ofthe wafers can be averaged to determine the Surface Roughness Index, anumber that can be associated with a grinding tool of the embodimentsherein.

EXAMPLES

Sample 1 is a high porosity resin bonded diamond superabrasive structuremade from a mixture of a superabrasive grain, ceria, a resin component,and a polymer blowing agent. Resin used in the microstructures isphenolformaldehyde. The physical blowing agents are PAN and PVDCcopolymer spheres from Dualite, of Henkel. The superabrasive grains arediamond having a size of 1-3 microns. The ceria has a size of 3-6microns. The composition of the mixture in volume percentage, beforeheating, is: 22.5% diamond, 2% ceria, 29% bond component, and 46.5% ofpolymer blowing agent.

To make the composite microstructures, material is weighed and mixed bystirring in a stainless steel bowl until a visually homogeneous mix isobtained. The mixture is screened through 165 mesh screen three times(US standard size). It is placed in a steel mold of a suitable design toyield test samples having the following dimensions: 5.020 inches×1.25inches×0.300 inches.

Each mixture is filled in the mold by spoon and is leveled in the moldusing a leveling paddle. The completely loaded mold package istransported to the electric press. Once the mold package is placed intothe press, two tons of pressure is applied, ensuring that the top platerode into the mold package evenly. The temperature is raised to 100° C.for 15 minutes, then to 150° C. for 10 minutes. The pressure applied tothe mold package was compacted. The temperature of the mold package wasraised to 180° C., and then soaked for 20 minutes. Once the soak cyclewas complete, the press was allowed to cool down to 100° C. by aircooling, followed by water cooling to room temperature. The mold packagewas removed from the press and transported to the “stripping” arborpress setup. The mold package (top and bottom plates plus the band) wasplaced onto the stripping arbor, strip band. The plates of the mold andsample were removed and ready to use.

The wheels are tested on a vertical spindle machine having two spindles.The first spindle uses a coarse grinding wheel and the second spindleuses a fine grinding wheel being tested. The silicon wafers are roughground with a coarse wheel followed by finishing with the fine wheel.The wheel is dressed using an extra-fine pad. The wheels are used togrind 8 inch silicon wafers. The average Ra of the samples is determinedto be 21 angstroms.

TABLE 1 Surface Roughness (Ra, angstroms) Sample 1 19 20 20 24 21 Sample2 21 21 20 23 23 Sample 3 21 21 22 21 22 Sample 4 23 22 24 22 20 Sample5 21 21 22 20 20

FIGS. 2 and 3 show scanning electron micrographs of the superabrasiveproduct 20. As can be seen in FIG. 2, the superabrasive product includeslarge pores 22 ranging in size from about 125 microns to about 150microns, intermediate pores 24 ranging in size from about 85 microns toabout 105 microns, and small pores 26 ranging in size from about 20microns to about 50 microns. As can be seen in FIG. 3, the pores 22, 24,and 26 have an arcuate inner surface that is relatively smooth comparedto the surface of the continuous phase outside of the pores. Further,the small particles 28 can be seen on the surface of the pores. Theparticles can include superabrasive grains and oxide particles.

Note that not all of the activities described above in the generaldescription or the examples are required, that a portion of a specificactivity may not be required, and that one or more further activitiesmay be performed in addition to those described. Still further, theorder in which activities are listed are not necessarily the order inwhich they are performed.

In the foregoing specification, the concepts have been described withreference to specific embodiments. However, one of ordinary skill in theart appreciates that various modifications and changes can be madewithout departing from the scope of the invention as set forth in theclaims below. Accordingly, the specification and figures are to beregarded in an illustrative rather than a restrictive sense, and allsuch modifications are intended to be included within the scope ofinvention.

As used herein, the terms “comprises,” “comprising,” “includes,”“including,” “has,” “having” or any other variation thereof, areintended to cover a non-exclusive inclusion. For example, a process,method, article, or apparatus that comprises a list of features is notnecessarily limited only to those features but may include otherfeatures not expressly listed or inherent to such process, method,article, or apparatus. Further, unless expressly stated to the contrary,“or” refers to an inclusive-or and not to an exclusive-or. For example,a condition A or B is satisfied by any one of the following: A is true(or present) and B is false (or not present), A is false (or notpresent) and B is true (or present), and both A and B are true (orpresent).

Also, the use of “a” or “an” are employed to describe elements andcomponents described herein. This is done merely for convenience and togive a general sense of the scope of the invention. This descriptionshould be read to include one or at least one and the singular alsoincludes the plural unless it is obvious that it is meant otherwise.

Benefits, other advantages, and solutions to problems have beendescribed above with regard to specific embodiments. However, thebenefits, advantages, solutions to problems, and any feature(s) that maycause any benefit, advantage, or solution to occur or become morepronounced are not to be construed as a critical, required, or essentialfeature of any or all the claims. After reading the specification,skilled artisans will appreciate that certain features are, for clarity,described herein in the context of separate embodiments, may also beprovided in combination in a single embodiment. Conversely, variousfeatures that are, for brevity, described in the context of a singleembodiment, may also be provided separately or in any subcombination.Further, references to values stated in ranges include each and everyvalue within that range.

1. A superabrasive resin product, comprising: a superabrasive graincomponent; an oxide component consisting of an oxide of a lanthanoid;and a continuous phase including a polymeric bond component, thecontinuous phase defines a network of interconnected pores, wherein thepores have a multimodal size distribution with at least two modes,wherein the superabrasive grain component and the oxide component aredistributed in the continuous phase.
 2. The superabrasive resin productof claim 1, wherein the lanthanoid includes an element having an atomicnumber of at least 57 and at most
 60. 3. The superabrasive resin productof claim 1, wherein the lanthanoid is at least one member selected fromthe group consisting of lanthanum, cerium, praseodymium, and neodymium.4. The superabrasive resin product of claim 1, wherein the lanthanoidincludes cerium.
 5. The superabrasive resin product of claim 8, whereinthe lanthanoid consists essentially of cerium.
 6. The superabrasiveresin product of claim 1, wherein the oxide component is present in anamount in a range of between about 0.05 and about 10.0 volume percent ofthe superabrasive product.
 7. The superabrasive resin product of claim1, wherein the oxide component has an average particle size in a rangeof between about 0.1 and about 30 microns.
 8. The superabrasive resinproduct of claim 1, wherein the continuous includes a thermoset polymercomponent.
 9. The superabrasive resin product of claim 8, wherein thethermoset polymer component includes at least one member selected fromthe group consisting phenol-formaldehyde, polyamide, polyimide andepoxy-modified phenolformaldehyde.
 10. The superabrasive resin productof claim 9, wherein the thermoset polymer component includespolyphenol-formaldehyde.
 11. The superabrasive resin product of claim 1,wherein the continuous phase includes a thermoplastic polymer componentand a thermoset resin component.
 12. The superabrasive resin product ofclaim 11, wherein the ratio of thermoset resin to thermoplastic polymercomponents in the continuous phase is in a range of between about 80:15and about 80:10 by volume.
 13. The superabrasive resin product of claim1, wherein the ratio of continuous phase to superabrasive component isin a range of between about 2:1 and about 1:2 by volume.
 14. Thesuperabrasive resin product of claim 1, wherein the continuous phase isa substantially open continuous phase.
 15. The superabrasive resinproduct of claim 1, wherein the superabrasive includes at least onemember selected from the group consisting of diamond, cubic boronnitride, zirconia and aluminum oxide.
 16. The superabrasive resinproduct of claim 14, wherein the superabrasive includes diamond.
 17. Thesuperabrasive resin product of claim 1, wherein the superabrasiveproduct has a porosity in a range of between about 30% and about 80% byvolume.
 18. The superabrasive product of any of claims 1 and 2, whereinthe product is a wheel.
 19. The superabrasive product of claim 18,wherein the superabrasive has a median particle size in a range ofbetween about 0.25 μm and about 30 μm.
 20. The superabrasive resinproduct of claim 11, wherein the thermoplastic polymer componentincludes polyacrylonitrile.